Power Plant with Multiple-Effect Evaporative Condenser

ABSTRACT

A power plant includes a power generating system, a tower housing and an evaporative cooling system which includes at least one multiple-effect evaporative condenser. The multiple-effect evaporative condenser includes a pumping device, a first cooling unit and a second cooling unit. The first cooling unit includes a first water collection basin for collecting said cooling water from the pumping device, a plurality of first heat exchanging pipes connected to the condenser and immersed in the first water collection basin, and a first fill material unit provided underneath the first heat exchanging pipes. The second cooling unit includes a second water collection basin positioned underneath the first cooling unit for collecting said cooling water flowing from the first cooling unit, a plurality of second heat exchanging pipes immersed in the second water collection basin, and a second fill material unit provided underneath the second heat exchanging pipes.

BACKGROUND OF THE PRESENT INVENTION Field of Invention

The present invention relates to a power plant, and more particularly to a power plant comprising at least one multiple-effect evaporative condenser which has a substantially improved energy efficiency and water consumption requirement as compared to conventional evaporative cooling tower for a power plant.

Description of Related Arts

Referring to FIG. 1 of the drawings, a conventional evaporative cooling tower for a power plant, such as a steam power plant having a condenser 203, is illustrated. The evaporative cooling tower generally comprises a main tower 301, a water collection basin 201 provided at a lower portion of the main tower 301, a plurality of fill material packs 208 provided above the water collection basin 201, a water distributing device 206 provided above the fill material packs 208, and a water pump 202 connected between the water collection basin 201 and the condenser 203. Cooling water in the water collection basin 201 is pumped by the water pump 202 to flow into the condenser 203 through a water inlet 203A. The cooling water absorbs heat from the condenser 203 and is pumped out thereof through a water outlet 203B. The cooling water is then pumped into the water distributing device 206 which sprays the cooling water on the fill material packs 208. The cooling water then forms a downwardly moving water film in the fill material packs 208. Ambient air is upwardly drawn from under the fill material packs 208 so that the ambient air which has a relatively lower temperature is arranged to perform heat exchange with the cooling water which has a relatively higher temperature in the fill material packs 208. Heat in the cooling water is carried away by the ambient air and this lowers the temperature of the cooling water. The cooling water is then allowed to drop into the water collection basin 201. The cooling water is then pumped back into the condenser 203 through the water inlet 203A and this completes a circulating cycle of the cooling water between the condenser 203 and the cooling tower 301.

The main tower 301 has a top ventilating opening 32. Ambient air is drawn from a lower portion of the main tower 301 and is arranged to perform heat exchange with the water film in the fill material packs 208. The air absorbs heat from the cooling water and flows to the upper portion of the main tower 301.

A major disadvantage for the above-mentioned conventional cooling tower is that the overall manufacturing and operating cost of the evaporative cooling tower is very high. Take a 600 MW power plant as an example, the circulation rate of the cooling water is approximately 78000 m³/hr. The overall power required by the water pump used in the evaporative cooling tower of this power plant is approximately 6900 kW. Furthermore, the overall size of a typical evaporative cooler is extremely huge and usually take the form of a hyperboloid structure. Although hyperboloid structures are said to minimize usage of material and maximize structural strength, their actual sizes are huge and it requires a substantial amount of land and space to accommodate even one evaporative cooling tower.

SUMMARY OF THE PRESENT INVENTION

An objective of the present invention is to provide a multiple-effect evaporative condenser which can be used in a power plant for effectively and efficiently rejecting heat from the power plant.

Another objective of the present invention is to provide a multiple-effect evaporative condenser which eliminates the need to have any hyperboloid cooling tower for a typical power plant. In other words, the overall size of the multiple-effect evaporative condenser can be substantially reduced as compared to conventional evaporative cooling towers.

Another objective of the present invention is to provide a multiple-effect evaporative condenser which utilizes a plurality of highly efficient heat exchanging pipes for providing a relatively large area of heat exchanging surfaces.

Another objective of the present invention is to provide a multiple-effect evaporative condenser which substantially lowers the volume and rate of cooling water circulation and the required power for water pumps. Thus, the present invention saves a substantial amount of energy as compared to conventional evaporative cooling towers for a given power plant.

Another objective of the present invention is to provide a highly efficient heat exchanging pipe which comprises a plurality of inner heat exchanging fins providing relatively large contact surface area. More specifically, the highly efficient heat exchanging pipe is capable of achieving critical heat flux density for a given material of the highly efficient heat exchanging pipe.

In one aspect of the present invention, the present invention provides a power plant, comprising:

a power generating system having a circulating heat exchange fluid;

a tower housing; and

a multiple-effect evaporative condenser having an air inlet side and an air outlet side which is opposite to the air inlet side, comprising:

an evaporative cooling system which comprises at least one multiple-effect evaporative condenser connected to the power generating system for effectively cooling the heat exchange, the multiple-effect evaporative condenser comprising:

an air inlet side and an air outlet side which is opposite to the air inlet side;

a pumping device adapted for pumping a predetermined amount of cooling water at a predetermined flow rate;

a first cooling unit, comprising:

a first water collection basin for collecting the cooling water from the pumping device;

a plurality of first heat exchanging pipes connected to the condenser and immersed in the first water collection basin; and

a first fill material unit provided underneath the first heat exchanging pipes, wherein the cooling water collected in the first water collection basin is arranged to sequentially flow through exterior surfaces of the first heat exchanging pipes and the first fill material unit;

a second cooling unit, comprising:

a second water collection basin positioned underneath the first cooling unit for collecting the cooling water flowing from the first cooling unit;

a plurality of second heat exchanging pipes immersed in the second water collection basin; and

a second fill material unit provided underneath the second heat exchanging pipes, wherein the cooling water collected in the second water collection basin is arranged to sequentially flow through exterior surfaces of the second heat exchanging pipes and the second fill material unit; and

a bottom water collecting basin positioned underneath the second cooling unit for collecting the cooling water flowing from the second cooling unit,

the cooling water collected in the bottom water collection basin being arranged to be guided to flow back into the first water collection basin of the first cooling unit, the heat exchange fluid from the evaporator being arranged to flow through the first heat exchanging pipes of the first cooling unit and the second heat exchanging pipes of the second cooling unit in such a manner that the heat exchange fluid is arranged to perform highly efficient heat exchanging process with the cooling water for lowering a temperature of the heat exchange fluid, a predetermined amount of air being drawn from the air inlet side for performing heat exchange with the cooling water flowing through the first fill material unit and the second fill material unit for lowering a temperature of the cooling water, the air having absorbed the heat from the cooling water being discharged out of the first fill material unit and the second fill material unit through the air outlet side.

In another aspect of the present invention, it provides an evaporative cooling system for a power plant having a power generating system and a tower housing, said evaporative cooling system comprising at least one multiple-effect evaporative condenser connected to the power generating system for effectively cooling the heat exchange fluid, the multiple-effect evaporative condenser comprising:

an air inlet side and an air outlet side which is opposite to the air inlet side;

a pumping device adapted for pumping a predetermined amount of cooling water at a predetermined flow rate;

a first cooling unit, comprising:

a first water collection basin for collecting the cooling water from the pumping device;

a plurality of first heat exchanging pipes connected to the condenser and immersed in the first water collection basin; and

a first fill material unit provided underneath the first heat exchanging pipes, wherein the cooling water collected in the first water collection basin is arranged to sequentially flow through exterior surfaces of the first heat exchanging pipes and the first fill material unit;

a second cooling unit, comprising:

a second water collection basin positioned underneath the first cooling unit for collecting the cooling water flowing from the first cooling unit;

a plurality of second heat exchanging pipes immersed in the second water collection basin; and

a second fill material unit provided underneath the second heat exchanging pipes, wherein the cooling water collected in the second water collection basin is arranged to sequentially flow through exterior surfaces of the second heat exchanging pipes and the second fill material unit; and

a bottom water collecting basin positioned underneath the second cooling unit for collecting the cooling water flowing from the second cooling unit,

the cooling water collected in the bottom water collection basin being arranged to be guided to flow back into the first water collection basin of the first cooling unit, the heat exchange fluid from the evaporator being arranged to flow through the first heat exchanging pipes of the first cooling unit and the second heat exchanging pipes of the second cooling unit in such a manner that the heat exchange fluid is arranged to perform highly efficient heat exchanging process with the cooling water for lowering a temperature of the heat exchange fluid, a predetermined amount of air being drawn from the air inlet side for performing heat exchange with the cooling water flowing through the first fill material unit and the second fill material unit for lowering a temperature of the cooling water, the air having absorbed the heat from the cooling water being discharged out of the first fill material unit and the second fill material unit through the air outlet side.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conventional cooling tower of a power plant.

FIG. 2 is a block diagram of a power plant according to the preferred embodiment of the present invention.

FIG. 3 is a schematic diagram of a cooling structure of a power plant according to a preferred embodiment of the present invention, illustrating that a tower housing has a plurality of multiple-effect evaporative condensers.

FIG. 4 is a schematic sectional view of five multiple-effect evaporative condensers along sectional plane A-A of FIG. 3.

FIG. 5 is a schematic diagram of one evaporative cooling system of the power plant according to a preferred embodiment of the present invention.

FIG. 6 is a plan view of a filter arrangement of the multiple-effect evaporative condensers according to the preferred embodiment of the present invention.

FIG. 7 is a side view of the filter arrangement of the multiple-effect evaporative condensers according to the preferred embodiment of the present invention.

FIG. 8 a side view of the multiple-effect evaporative condensers according to the preferred embodiment of the present invention, illustrating a cleaning device of the filtering arrangement.

FIG. 9 a schematic diagram of the cleaning device of the filter arrangement according to the preferred embodiment of the present invention.

FIG. 10 a plan view of the first passage plate of the first water collection basin according to the preferred embodiment of the present invention.

FIG. 11 is a partial side view of a flow control mechanism of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 12 is a first schematic diagram of the flow control mechanism of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 13 is a partial plan view of the flow control mechanism of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 14 is second schematic diagram of the flow control mechanism of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 15 is third schematic diagram of the flow control mechanism of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 16 is a sectional view of a heat exchanging pipe of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 17 is a schematic diagram of a first guiding system of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 18 is another schematic diagram of the first guiding system of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 19 is a schematic diagram of a second guiding system of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 20 is another schematic diagram of the second guiding system of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

FIG. 21 is an alternative mode of a first water collection basin of the multiple effect evaporative condenser according to the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following detailed description of the preferred embodiment is the preferred mode of carrying out the invention. The description is not to be taken in any limiting sense. It is presented for the purpose of illustrating the general principles of the present invention.

Referring to FIG. 2 to FIG. 21 of the drawings, a power plant according to a preferred embodiment of the present invention is illustrated. Broadly, the power plant, such as a steam power plant, comprises a power generating system 10 having a predetermined amount of heat exchange fluid, a tower housing 3 having an air inlet 31 and an air outlet 32, and an evaporative cooling system 40 which comprises at least one multiple-effect evaporative condenser 1 which is accommodated in the tower housing 3 and is connected to the power generating system 10 for lowering a temperature of the predetermined heat exchange fluid, such as saturated steam. The power generating system 10 may comprise a turbine, an electric generator, and a heat exchange fluid generator, such as a steam generator. For a typical steam power plant, the heat exchange fluid may be steam or vapor. The heat exchange fluid is circulated between various components of the power plant for performing heat exchange with different mediums and may do work on the turbine for generating electricity.

The multiple-effect evaporative condenser 1 comprises an air inlet side 101, an air outlet side 102 which is opposite to the air inlet side 101, a pumping device 601 adapted for pumping a predetermined amount of cooling water at a predetermined flow rate and volume, a first cooling unit 51, a second cooling unit 52, and a bottom water collection basin 53.

The first cooling unit 51 comprises a first water collection basin 511 for collecting the cooling water from the pumping device 601, a plurality of first exchanging pipes 512, and a first fill material unit 513. The heat exchanging pipes 512 are connected to the heat generating system 10 and immersed in the first water collection basin 511.

The first fill material unit 513 is provided underneath the first heat exchanging pipes 512, wherein the cooling water collected in the first water collection basin 511 is arranged to sequentially flow through exterior surfaces of the first heat exchanging pipes 512 and the first fill material unit 513.

The second cooling unit 52 comprises a second water collection basin 521, a plurality of second heat exchanging pipes 522, and a second fill material unit 523. The second water collection basin 521 is positioned underneath the first cooling unit 51 for collecting the cooling water flowing from the first cooling unit 51. The plurality of second heat exchanging pipes 522 are immersed in the second water collection basin 521.

The second fill material unit 523 is provided underneath the second heat exchanging pipes 522, wherein the cooling water collected in the second water collection basin 521 is arranged to sequentially flow through exterior surfaces of the second heat exchanging pipes 522 and the second fill material unit 523.

The bottom water collecting basin 53 is positioned underneath the second cooling unit 52 for collecting the cooling water flowing from the second cooling unit 52.

The cooling water collected in the bottom water collection basin 53 is arranged to be guided to flow back into the first water collection basin 511 of the first cooling unit 51, while the heat exchange fluid from the power generating system 10 is arranged to flow through the first heat exchanging pipes 512 of the first cooling unit 51 and the second heat exchanging pipes 522 of the second cooling unit 52 in such a manner that the heat exchange fluid is arranged to perform highly efficient heat exchanging process with the cooling water for lowering a temperature of the heat exchange fluid. At the same time, a predetermined amount of air is drawn from the air inlet side 101 for performing heat exchange with the cooling water flowing through the first fill material unit 513 and the second fill material unit 523 for lowering a temperature of the cooling water. The air having absorbed the heat from the cooling water is discharged out of the first fill material unit 513 and the second fill material unit 523 through the air outlet side 102.

According to the preferred embodiment of the present invention, the evaporative cooling system 40 comprises a plurality of multiple-effect evaporative condensers 1 accommodated in the tower housing 3. As shown in FIG. 3 of the drawings, the tower housing 3 has a generally circular cross sectional shape. The multiple-effect evaporative condensers 1 are spacedly arranged in the tower housing 3 in two rows and a plurality of columns such that technicians can pass through the space (hereinafter referred to central aisle 304 of the tower housing 3) formed between each row of the multiple-effect evaporative condensers 1 and the spaces (hereinafter referred to branch aisles 305 of the tower housing 3) formed between each column of the multiple-effect evaporative condensers 1. This arrangement allows easy access by the technicians for maintenance of each of the multiple-effect evaporative condensers 1. Thus, for each row of the multiple-effect evaporative condensers 1, a longitudinal axis of each of the multiple-effect evaporative condensers 1 is substantially parallel to each other. For each column of the multiple-effect evaporative condensers 1, a longitudinal axis of each of the multiple-effect evaporative condensers 1 is substantially aligned.

It is important to mention, however, that the particular arrangement of multiple-effect evaporative condensers 1 may vary depending on the circumstances in which the power plant and the multiple-effect evaporative condensers 1 are operated.

Referring to FIG. 4 of the drawings, five multiple-effect evaporative condensers 1 are illustrated. Each of the multiple-effect evaporative condensers 1 actually comprises a plurality of cooling units (in additional to the first cooling unit 51 and the second cooling unit 52 described above) positioned between the first water collection basin 511 and the bottom water collection basin 53.

As shown in FIG. 3 of the drawings, each two adjacent multiple-effect evaporative condensers 1 may be grouped to form an evaporative condenser unit 8 so that each of the evaporative condenser units 8 is linked by a top sealing member 701 which is connected between two first water collection basins 511 of the two adjacent multiple-effect evaporative condensers 1 respectively. In other words, each of the top sealing members 701 covers the top portion of the aisle formed between two air inlet sides 101 of two multiple-effect evaporative condensers 1 of each evaporative condenser unit 8. The purpose of the top sealing members 701 is to prevent incoming air (from the central aisle 304) from escaping through the opening covered by the top sealing members 701. As a result, the air is guided or forced to pass through the first fill material unit 513 and the second fill material unit 523 and exit the relevant multiple-effect evaporative condenser 1 from the air outlet side 102 thereof. Thus, the branch aisle 305 which is formed between each two evaporative condenser unit 8 is not covered by any top sealing member 701. This arrangement allows or guides relatively warm air to flow out of the tower housing 3 through the air outlet 32 without trapping in the tower housing 3.

The pumping device 601 is preferably positioned in the bottom water collection basin 53 at the air inlet side 101, and is connected to the first water collection basin 511 through a water pipe 602. It is worth mentioning that the operation of each of the multiple-effect evaporative condensers 1 may be separately controlled so that when maintenance is required, technicians may simply turn off one or more multiple-effect evaporative condensers 1 for replacing the pumping device 601, the cooling units 51 (52), or any other components.

From typical engineering standards, a conventional cooling tower for a 600 MW power plant requires approximately 280 m³ of cooling water circulating the power plant and the cooling tower. For the present invention, it is estimated that the total volume of cooling water required for the power plant having the same power generating capacity is only approximately 78 m³, because the rate at which the cooling water circulates is only approximately 4300 m³/hr. Since the rate at which the cooling water circulates is relatively low, the water pipe 602 may be made of plastic or composite material so as to further lower the manufacturing and maintenance cost of the entire system.

According to the preferred embodiment of the present invention, each of the multiple-effect evaporative condensers 1 comprises first through fifth cooling units 51, 52, 6, 7, 9. The number of cooling units utilized depend on the circumstances in which the air conditioning system is operated. FIG. 4 illustrates a situation where the multiple-effect evaporative condenser 1 comprise five cooling units, namely, the first cooling unit 51, the second cooling unit 52, the third cooling unit 6, the fourth cooling unit 7, and the fifth cooling unit 9. In practical use, the number of cooling units may be as many as fifteen, or even more.

When the cooling water passes through one cooling unit, its temperature is arranged to increase by absorbing heat from the relevant heat exchanging pipes and is to be lowered by a predetermined temperature gradient by extracting heat to the ambient air (referred to as one “temperature cooling effect” on the cooling water), so that if the cooling water passes through five cooling units 51, 52, 6, 7, 9, the multiple-effect evaporative condenser 1 has a total of five temperature effects on the cooling water because the cooling water is heated up by the heat exchanging pipes five times and cooled down by the ambient air in the relevant fill material unit five times.

Referring to FIG. 4 of the drawings, the third cooling unit 6 comprises a third water collection basin 61, a plurality of third heat exchanging pipes 62 immersed in the third water collection basin 61, and a third fill material unit 63 provided under the third water collection basin 61. The fourth cooling unit 7 comprises a fourth water collection basin 71, a plurality of fourth heat exchanging pipes 72 immersed in the fourth water collection basin 71, and a fourth fill material unit 73 provided under the fourth water collection basin 71. The fifth cooling unit 9 comprises a fifth water collection basin 91, a plurality of fifth heat exchanging pipes 92 immersed in the fifth water collection basin 91, and a fifth fill material unit 93 provided under the fifth water collection basin 91. Note that where the multiple-effect evaporative condenser 5 has more than five cooling units, each of the additional cooling units will have the same structure as that of first through fifth cooling units 51, 52, 7, 8, 9. For example, a sixth cooling unit may comprise a sixth water collection basin, a plurality of sixth heat exchanging pipes, and a sixth fill material unit, so on and so forth.

The cooling water is pumped by the pumping device 601 to flow into the first water collection basin 511 of the first cooling unit 51. The cooling water is arranged to perform heat exchange with the heat exchange fluid flowing through the first heat exchanging pipes 512 and absorb a certain amount of heat. The cooling water is then allowed to flow into the first fill material unit 513 where it forms thin water film under the influence of gravity. The water film performs heat exchange with the air draft so that heat is extracted from the cooling water to the ambient air. The cooling water is then guided to flow into the second water collection basin 521 of the second cooling unit 52 and performs another cycle of heat exchange with the heat exchange fluid flowing through the second heat exchanging pipes 522 and in the second fill material unit 523. The cooling water is guided to sequentially flow through first through fifth cooling unit 51, 52, 6, 7, 9 to absorb heat from the heat exchange fluid flowing through the various heat exchanging pipes.

Furthermore, each of the multiple-effect evaporative condensers 1 further comprises at least one filter arrangement 54 detachably supported between the first cooling unit 51 and the second cooling unit 52 for filtering unwanted substances from the cooling water flowing from the first cooling unit 51 to the second cooling unit 52, as shown in FIG. 5 to FIG. 8 of the drawings.

The filter arrangement 54 comprises a main panel 541, a plurality of through filtering holes 542 spacedly formed on the main panel 541, a filtering net 543 attached on a bottom side of the main panel 541, and a supporting member 544 provided at a bottom side of the main panel 541. The cooling water from the first cooling unit 51 is arranged to pass through the filtering holes 542 so that large particles are stopped at the filtering holes 542. After that, the cooling water is then arranged to pass through the filtering net 543 to reach the second cooling unit 52.

Referring to FIG. 7 to FIG. 9 of the drawings, the filter arrangement 54 further comprises a cleaning arrangement 545 which is used for periodically cleaning the filtering net 543. Specifically, the cleaning arrangement 545 comprises a plurality of guiding pulleys 5451 provided at two ends of the filtering net 543, a plurality of cleaning nozzles 5452 supported at a position adjacent to the guiding pulleys 5451 respectively.

It is important to mention at this point that the cleaning arrangement 545 is particularly suitable for use in a multiple-effect evaporative condenser 1 which comprises at least three cooling units 51, 52, 6, 7, 9. FIG. 9 illustrates five cooling units so that a lengthy filtering net 543 is used to pass through each guiding pulley 5451. In other words, the filtering net 543 is divided into a plurality of filtering sections 5431 wherein each filtering section 5431 is securely supported in between each two corresponding cooling units 51, 52, 6, 7, 9 by two corresponding guiding pulleys 5451. When the guiding pulleys 5451 is driven to rotate by a pulley driving unit 548, they drive the filtering net 543 to move along the guiding pulleys 5451. At the same time, the cleaning nozzles 5452 are activated to eject fluid, such as water, at a predetermined speed so as to remove particles trapped by the filtering net 543.

In this particular arrangement, the filtering net 543 may be configured by stainless steel which has sufficient rigidity. In this situation, the main panel 541 described above may be omitted. Moreover, the filter arrangement 54 further comprises a plurality of supporting stems 546 provided on two sides of the multiple-effect evaporative condenser 1 for supporting the filtering net 543 through a plurality of connectors 547.

As shown in FIG. 5 of the drawings, the first water collection basin 511 has a first stabilizing compartment 5111 connected to the pumping device 601, a first heat exchanging compartment 5112 provided adjacent to and communicated with the first stabilizing compartment 5111 via a first water channel 5113, wherein the first heat exchanging pipes 512 are immersed in the first heat exchanging compartment 5112. The cooling water pumped by the pumping device 601 is guided to flow into the first stabilizing compartment 5111. When the stabilizing compartment 5111 is filled with a predetermined amount of cooling water which reaches the first water channel 5113, the cooling water flows into the heat exchanging compartment 5112 through the first water channel 5113. The purpose of the first stabilizing compartment 5111 is to provide a buffer zone for controlling the flow rate and pressure of the cooling water. These parameters affect the performance of the heat exchanging process between the cooling water and the first heat exchanging pipes 512.

It is worth mentioning that the first water channel 5113 should be elongated in shape and extend along a longitudinal direction of the first water collection basin 511 so as to allow the cooling water to evenly flow into the first heat exchanging compartment 5112 along a longitudinal direction of the first heat exchanging pipes 512. As a result, the cooling water enters the first heat exchanging compartment 5112 at an even flow rate along the entire length of the first heat exchanging pipes 512. This structural arrangement also ensures that the first heat exchanging pipes 512 are immersed in the cooling water in its entirety.

The first water collection basin 511 has a first inner sidewall 5114, a first outer sidewall 5115, a first partitioning wall 5116, a first bottom plate 5117, and a first passage plate 5118. The first partitioning wall 5116 is provided between the first inner sidewall 5114 and the first outer sidewall 5115, and divides the first water collection basin 511 into the first stabilizing compartment 5111 and the first heat exchanging compartment 5112, wherein the first water channel 5113 is formed on the first partitioning wall 5116 along a longitudinal direction thereof. The first stabilizing compartment 5111 is formed between the first inner sidewall 5114, the first partitioning wall 5116, and the first bottom plate 5117. The first heat exchanging compartment 5112 is formed by the first partitioning wall 5116, the first outer sidewall 5115, and the first passage plate 5118.

In this preferred embodiment of the present invention, the first stabilizing compartment 5111 is formed at a side portion of the first water collection basin 511 along a longitudinal direction thereof. The first stabilizing compartment 5111 and the first heat exchanging compartment 5112 are divided by the first partitioning wall 5116.

The first passage plate 5118 has a plurality of first passage holes 5119 for allowing the cooling water contained in the first heat exchanging compartment 5112 to fall into the first fill material unit 513. Referring to FIG. 10 to FIG. 13 of the drawings, the first passage holes 5119 are distributed along the first passage plate 5118 in a predetermined array, wherein a center of each of the first passage holes 5119 in a particular row is arranged not to align with that of the first passage holes 5119 in the next row. Moreover, each two adjacent first passage holes 5119 of an upper row thereof is arranged to form a triangular distribution with a corresponding first passage hole 5119 of the adjacent row of the first passage holes 5119. The first passage holes 5119 all have identical shape and size.

Referring to FIG. 9 to FIG. 15 of the drawings, each of the multiple-effect evaporative condensers 1 comprises a flow control mechanism 55 which comprises at least one control plate 551 movably provided underneath the first passage plate 5118 of the first water collection basin 511, and at least one driving member 552 connected to the control plate 551 for driving the control plate 551 to move in a horizontal and reciprocal manner. The control plate 551 has a plurality of control holes 5511 spacedly distributed thereon. The number, size, and shape of the control holes 5511 are identical to those of the first passage holes 5119. Moreover, centers of the first passage holes 5119 are normally aligned with those of the control holes 5511 respectively. The flow control mechanism 55 further comprises a plurality of securing members 553 mounted on the first water collection basin 551 and is arranged to normally exert an upward biasing force toward the control plate 551 so as to maintain a predetermined distance between the control plate 551 and the first passage plate 5118.

In this preferred embodiment, the driving member 552 comprises an adjustment screw adjustably connected between the first water collection basin 511 and the control plate 551 for driving the control plate 551 to move in a horizontal and reciprocal manner.

As shown in FIG. 10 of the drawings, when each of the first passage holes 5119 is aligned or substantially overlap with a corresponding control hole 5511, the cooling water in the first water collection basin 511 may pass through the first passage plate 5118 and the control plate 551 at maximum flow rate. However, as shown in FIG. 12 of the drawings, when the control plate 551 is driven to move horizontally, the control holes 5511 and the first passages holes 5119 no longer align and flow rate of the cooling water passing through the control plate 551 and the first passage plate 5118 will decrease. When the control plate 551 is moved such that each of the control holes 5511 blocks the corresponding first passage hole 5119, the flow rate of the cooling water is at its minimum, which is approximately one-third of the maximum flow rate of the cooling water.

The purpose of the flow control mechanism 55 is to control the flow rate of the cooling water flowing from the first cooling unit 51 to the second cooling unit 52, or from an upper cooling unit to a lower cooling unit. The controlled flow rate ensures that the heat exchanging pipes, such as the second heat exchanging pipes 522, can be fully immersed in the cooling water so as to perform the heat exchange process in the most effective and efficient manner. Generally speaking, the flow control mechanism 55 comprises the same number of control plates 551 as that of the cooling units 51, 52, 6, 7, 9. In other words, when the multiple-effective evaporative condensers 1 comprises first through fifth cooling units 51, 52, 6, 7, 9, the flow control mechanism will comprise five control plates 551 and five driving members 552. The structure of each of the control plates 551 and the driving members 552 is identical and has been described above.

Referring to FIG. 5 of the drawings, the first water collection basin 511 further has a pair of first securing slots 5110 formed at lower portions of the first partitioning wall 5116 and the first outer sidewall 5115 respectively. Each of the first securing slots 5110 is elongated along a longitudinal direction of the first water collection basin 511, wherein the securing members 553 are mounted in the first securing slots 5110 respectively. In this preferred embodiment, each of the securing members 553 is a resilient element which normally exerts an upward biasing force against the control plate 551.

The first water collection basin 511 (or other water collection basins used in the present invention) can be manufactured as an integral body for ensuring maximum structural integrity and minimum manufacturing cost. The material used may be plastic material or stainless steel.

Referring to FIG. 14 to FIG. 15 of the drawings, the flow control mechanism 55 further comprises an automated control system 554 operatively connected to at least one driving member 552. The automated control system 554 comprises a central control unit 5541, a connecting member 5542 connected between the central control unit 5541 and the driving member 552, and a sensor 5543 provided in the first water collection basin 511 and electrically connected to the central control unit 5541.

The sensor 5543 detects the water level in the first water collection basin 511 and sends a signal to the central control unit 5541, which is pre-programmed to respond to the sensor signal. The central control unit 5541 is then arranged to drive the connecting member 5542 to move horizontally so as to drive the driving member 552 to move in the same direction for controlling the flow rate of the cooling water flowing through the first passage plate 5118.

The multiple effect evaporative condenser 1 further comprises a plurality of inspection windows 56 formed on the first water collection basin 511 and the second water collection basin 521 for allowing a technician to visually observe the water level in the first water collection basin 511 and the second water collection basin 521 respectively. Each of the inspection windows 56 may include a transparent glass for allowing the technician to visually observe the water level from an exterior of the corresponding water collection basin. Note that the inspection windows 56 may be formed on each cooling unit.

As shown in FIG. 4 of the drawings, the second water collection basin 521 has a second heat exchanging compartment 5211, wherein the second heat exchanging pipes 522 are immersed in the second heat exchanging compartment 5211. The cooling water coming from the first cooling unit 51 is guided to flow into the second heat exchanging compartment 5211 via the filter arrangement 54.

The second water collection basin 521 has a second inner sidewall 5212, a second outer sidewall 5213, and a second passage plate 5214. The second heat exchanging compartment 5211 is defined within the second inner sidewall 5212, the second outer sidewall 5213, and the second passage plate 5214. The second passage plate 5214 has a plurality of second passage holes 5215 for allowing the cooling water contained in the second heat exchanging compartment 5211 to fall into the bottom water collection basin 53 or an additional cooling unit, such as the third cooling unit 6, when the multiple-effective evaporative condenser 1 has more than two cooling units.

Referring to FIG. 10 of the drawings, the second passage holes 5215 are distributed along the second passage plate 5214 in a predetermined array, wherein a center of each of the second passage holes 5215 in a particular row is arranged not to align with that of the second passage holes 5215 in the next row. Moreover, each two adjacent second passage holes 5215 of an upper row thereof is arranged to form a triangular distribution with a corresponding second passage hole 5215 of the adjacent row of the second passage holes 5215. The second passage holes 5215 all have identical shape and size. These structures are identical to that of the first passage plate 5118, and the first passage holes 5119.

Referring to FIG. 8 of the drawings, the second water collection basin 521 further has a pair of second securing slots 5216 formed at lower portions of the second inner side wall 5212 and the second outer sidewall 5213 respectively. Each of the second securing slots 5216 is elongated along a longitudinal direction of the second water collection basin 521, wherein the corresponding securing members 553 are mounted in the second securing slots 5216 respectively. Again, in this preferred embodiment, each of the securing members 553 is a resilient element which normally exert an upward biasing force against the corresponding control plate 551.

As mentioned above, the flow control mechanism 55 may be operated through the automated control system 554 operatively connected to all the driving members 552 for electrically and automatically controlling the movement of all of the driving members and ultimately the control plates 551.

In order to ensure the water level in each of the water collection basins 511, 521, each of the multiple effect evaporative condensers 1 further comprises a supplementary water supply unit 20 which comprises a plurality of water level sensors 21 provided in the first water collection basin 511 and the second water collection basin 521 respectively, a plurality of supplemental water pipes 22 extended between the water pipe 602 and the first water collection basin 511 and the second water collection basin 521 respectively, and a plurality of water control valves 23 provided in the supplemental water pipes 22 respectively for controlling a flow of water therein. When the water level in either the first water collection basin 511 or the second water collection basin 521 is too low, the water control valves 23 are activated to allow a predetermined amount of water to pass through the supplemental water pipes 22 so as to ensure adequate supply of water is maintained in the first water collection basin 511 and the second water collection basin 521. It is important to mention that the supplemental water pipes 22 and the water level sensor 21 may be provided for each cooling unit of the multiple effect evaporative condenser 1.

Referring to FIG. 16 of the drawings, each of the first heat exchanging pipes 512 comprises a first pipe body 5121 and a plurality of first retention members 5122 spacedly formed in the first pipe body 5121, and a plurality of first heat exchanging fins 5123 extended from an inner surface 5124 of the first pipe body 5121. Specifically, the first pipe body 5121 has two curved side portions 5125 and a substantially flat mid portion 5126 extending between the two curved side portions 5125 to form rectangular cross sectional shape at the mid portion 5126 and two semicircular cross sectional shapes at two curved side portions 5125 of the first heat exchanging pipe 512.

Furthermore, the first retention members 5122 are spacedly distributed in the flat mid portion 5126 along a transverse direction of the corresponding first pipe body 5121 so as to form a plurality of first pipe cavities 5127. Each of the first retention members 5122 has a predetermined elasticity for reinforcing the structural integrity of the corresponding first heat exchanging pipe 512. On the other hand, each of the first heat exchanging fins 5123 are extended from an inner surface of the first pipe body 5121. The first heat exchanging fins 5123 are spacedly and evenly distributed along the inner surface 5124 of first pipe body 5121 for enhancing heat exchange performance between the heat exchange fluid flowing through the corresponding first heat exchanging pipe 512 and the cooling water.

When the first heat exchanging pipes 512 operate under vacuum condition, or when the first heat exchanging pipes 512 are subject to higher external pressure (meaning negative pressure inside the pipes 512), the first heat exchanging fins 5123 and the corresponding retention members 5122 may be used to withstand a certain amount of external pressure so as to reinforcing the structural integrity of the first heat exchanging pipes 512. The length of the first heat exchanging fins 5123 depend on the actual circumstances in which the first heat exchanging pipes 512 are used.

On the other hand, when the first heat exchanging pipes 512 are subject to positive pressure inside the pipes 512, the first retention members 5122, having a predetermined elasticity, will exert a pulling force to the first pipe body 5121 and therefore may assist in withstanding such positive pressure developed inside the first pipe body 5121.

On the other hand, the second heat exchanging pipes 522 are structurally identical to the first heat exchanging pipes 512. So, also referring to FIG. 16 of the drawings, each of the second heat exchanging pipes 522 comprises a second pipe body 5221 and a plurality of second retention members 5222 spacedly formed in the second pipe body 5221, and a plurality of second heat exchanging fins 5223 extended from an inner surface 5224 of the pipe body 5221. The second pipe body 5221 has two curved side portions 5225 and a substantially flat mid portion 5226 extending between the two curved side portions 5225 to form rectangular cross sectional shape at the mid portion 5226 and two semicircular cross sectional shapes at two curved side portions 5225 of the second heat exchanging pipe 522.

Furthermore, the retention members 5222 are spacedly distributed in the flat mid portion 5226 along a transverse direction of the corresponding pipe body 5221 so as to form a plurality of second pipe cavities 5227. Each of the retention members 5222 has a predetermined elasticity for reinforcing the structural integrity of the corresponding second heat exchanging pipe 522. On the other hand, each of the second heat exchanging fins 5223 are extended from an inner surface of the second pipe body 5221. The second heat exchanging fins 5223 are spacedly and evenly distributed along the inner surface 5224 of second pipe body 5221 for enhancing heat exchange performance between the heat exchange fluid flowing through the corresponding second heat exchanging pipe 522 and the cooling water.

It is worth mentioning that when the multiple-effect evaporative condenser 1 comprises many cooling units, such as the above-mentioned first through fifth cooling units 51, 52, 6, 7, 9, the third through fifth heat exchanging pipes 62, 72, 92 are structurally identical to the first heat exchanging pipes 512 and the second heat exchanging pipes 522 described above.

According to the preferred embodiment of the present invention, each of the first through fifth heat exchanging pipes 512, 522, 62, 72, 92 are configured from aluminum which can be recycled and reused very conveniently and economically. In order to make the heat exchanging pipes to resist corrosion and unwanted oxidation, each of the heat exchanging pipes 512, 522, 62, 72, 92 has a thin oxidation layer formed on an exterior surface and an interior surface thereof for preventing further corrosion of the relevant heat exchanging pipe. The formation of this thin oxidation layer can be by anode oxidation method.

Moreover, each of the heat exchanging pipes 512, 522, 62, 72, 92 may also have a thin layer of polytetrafluoroethylene formed on an exterior surface and/or interior surface thereof to prevent unwanted substances from attaching on the exterior surfaces of the heat exchanging pipes 512, 522, 62, 72, 92.

The use of aluminum for the heat exchanging pipes 512, 522, 62, 72, 92 allows reduction of manufacturing cost by approximately 70% as compared with traditional heat exchanging pipes, which are configured from copper. Possible corrosion problem is effectively resolved by the introduction of the thin oxidation layer on an exterior surface and an interior surface of each of the heat exchanging pipes and the addition of the thin layer of thin layer of polytetrafluoroethylene on the exterior surfaces of the heat exchanging pipes.

Referring to FIG. 17 of the drawings, it illustrates that the first heat exchanging pipes 512 and the second heat exchanging pipes 522 are connected in parallel. As a result, the heat exchange fluid enters the relevant multiple-effect evaporative condenser 1 and passes through the first through second heat exchanging pipes 512, 522 at the same time. After passing through each of the first through second heat exchanging pipes 512, 522, the temperature of the heat exchange fluid will be substantially lowered and the heat exchange fluid is arranged to exit the multiple-effect evaporative condenser 1.

Referring to FIG. 17 to FIG. 18 of the drawings, the first cooling unit 51 further comprises a first guiding system 514 connected to the first heat exchanging pipes 512 to divide the first heat exchanging pipes 512 into several piping groups so as to guide the heat exchange fluid to flow through the various piping groups in a predetermined order. Specifically, the first guiding system 514 comprises a plurality of first inlet collection pipes 5141 extended between outer ends of the first heat exchanging pipes 512, a first outlet pipe 5142 extended between inner ends of the first heat exchanging pipes 512. Note that the first inlet collection pipes 5141 and the first outlet pipe 5142 are substantially parallel to each other in which the first outlet pipe 5142 is extended at a position between the two first inlet collection pipes 5141.

According to the preferred embodiment of the present invention, there ten first heat exchanging pipes 512 in the first cooling unit 51. The ten heat exchanging pipes 512 are divided into two piping groups in which each piping group contains five heat exchanging pipes 512 which are extended between a first inlet collection pipe 5141 and a first outlet pipe 5142. Five of the first heat exchanging pipes 512 are extended between one of the first inlet collection pipes 5141 and the first outlet pipe 5142 at a transverse direction thereof, while another five of the first heat exchanging pipes 512 are extended between another first inlet collection pipes 5141 and the first outlet pipe 5142 from the other side thereof. This configuration is graphically depicted in FIG. 17 of the drawings. The first heat exchanging pipes 512 are inclinedly and downwardly extended from the first inlet collection pipe 5141 toward the first outlet pipe 5142.

The heat exchange fluid is arranged to enter the first heat exchanging pipes 512 through the first inlet collection pipes 5141. The heat exchange fluid is arranged to flow through the first heat exchanging pipes 512 and perform heat exchange with the cooling water as described above. After that, the heat exchange fluid is arranged to leave the first cooling unit 51 through the first outlet pipe 5142.

In addition, the first guiding system 514 further comprises a plurality of first heat exchanging fins 5123 extended between each two adjacent first heat exchanging pipes 512 for substantially increasing a surface area of heat exchange between the first heat exchanging pipes 512 and the cooling water, and for reinforcing a structural integrity of the first guiding system 514. These first heat exchanging fins 5223 may be integrally extended from an outer surface of the first heat exchanging pipes 512, or externally attached or welded on the outer surfaces of the first heat exchanging pipes 512.

Referring to FIG. 19 to FIG. 20 of the drawings, the second cooling unit 52 further comprises a second guiding system 524 connected to the second heat exchanging pipes 522 to divide the second heat exchanging pipes 522 into several piping groups so as to guide the heat exchange fluid to flow through the various piping groups in a predetermined order. Specifically, the second guiding system 524 comprises a plurality of second inlet collection pipes 5241 extended between outer ends of the second heat exchanging pipes 522, a second outlet pipe 5242 extended between inner ends of the second heat exchanging pipes 522. Note that the second inlet collection pipes 5241 and the second outlet pipe 5242 are substantially parallel to each other in which the second outlet pipe 5242 is extended at a position between the two second inlet collection pipes 5241.

According to the preferred embodiment of the present invention, there ten second heat exchanging pipes 522 in the second cooling unit 52. The ten heat exchanging pipes 522 are divided into two piping groups in which each piping group contains five heat exchanging pipes 522 which are extended between a second inlet collection pipe 5241 and a second outlet pipe 5242. Five of the second heat exchanging pipes 522 are extended between one of the second inlet collection pipes 5241 and the second outlet pipe 5242 at a transverse direction thereof, while another five of the second heat exchanging pipes 522 are extended between another second inlet collection pipes 5241 and the second outlet pipe 5242 from the other side thereof. This configuration is graphically depicted in FIG. 17 of the drawings. The second heat exchanging pipes 522 are inclinedly and downwardly extended from the second inlet collection pipe 5241 toward the second outlet pipe 5242.

The heat exchange fluid is arranged to enter the second heat exchanging pipes 522 through the second inlet collection pipes 5241. The heat exchange fluid is arranged to flow through the second heat exchanging pipes 522 and perform heat exchange with the cooling water as described above. After that, the heat exchange fluid is arranged to leave the second cooling unit 52 through the second outlet pipe 5242.

In addition, the second guiding system 524 further comprises a plurality of second heat exchanging fins 5223 extended between each two adjacent second heat exchanging pipes 522 for substantially increasing a surface area of heat exchange between the second heat exchanging pipes 522 and the cooling water, and for reinforcing a structural integrity of the second guiding system 524. These second heat exchanging fins 5223 may be integrally extended from an outer surface of the second heat exchanging pipes 522, or externally attached or welded on the outer surfaces of the second heat exchanging pipes 522.

It is important to mention that the above-mentioned configuration of the first guiding system 51, the second guiding system 524, the first heat exchanging pipes 512, the second heat exchanging pipes 522, and the number of piping groups are for illustrative purpose only and can actually be varied according to the circumstances in which the present invention is operated.

Referring to FIG. 21 of the drawings, an alternative mode of the power plant according to the preferred embodiment of the present invention is illustrated. The alternative mode is identical to the preferred embodiment as described above except the first water collection basin 511′. According to the alternative mode, the first stabilizing compartment 5111′ of the first water collection basin 511 is indently formed at a side portion of the first water collection basin 511′ along a longitudinal direction thereof, wherein the first stabilizing compartment 5111′ is connected to the water pipe 602 for allowing the cooling water to enter the first water collection basin 511′ at the first stabilizing compartment 5111′. In other words, the first stabilizing compartment 5111′ is configured as an indention or slot which communicates with the first heat exchanging compartment 5112.

The present invention, while illustrated and described in terms of a preferred embodiment and several alternatives, is not limited to the particular description contained in this specification. Additional alternative or equivalent components could also be used to practice the present invention. 

What is claimed is:
 1. A power plant, comprising: a power generating system having a circulating heat exchange fluid; a tower housing; and an evaporative cooling system which comprises at least one multiple-effect evaporative condenser connected to said power generating system for effectively cooling said heat exchange fluid, said multiple-effect evaporative condenser comprising: an air inlet side and an air outlet side which is opposite to said air inlet side; a pumping device adapted for pumping a predetermined amount of cooling water at a predetermined flow rate; a first cooling unit, comprising: a first water collection basin for collecting said cooling water from said pumping device; a plurality of first heat exchanging pipes connected to said power generating system and immersed in said first water collection basin; and a first fill material unit provided underneath said first heat exchanging pipes, wherein said cooling water collected in said first water collection basin is arranged to sequentially flow through exterior surfaces of said first heat exchanging pipes and said first fill material unit; a second cooling unit, comprising: a second water collection basin positioned underneath said first cooling unit for collecting said cooling water flowing from said first cooling unit; a plurality of second heat exchanging pipes immersed in said second water collection basin; and a second fill material unit provided underneath said second heat exchanging pipes, wherein said cooling water collected in said second water collection basin is arranged to sequentially flow through exterior surfaces of said second heat exchanging pipes and said second fill material unit; and a bottom water collecting basin positioned underneath said second cooling unit for collecting said cooling water flowing from said second cooling unit, the cooling water collected in said bottom water collection basin being arranged to be guided to flow back into said first water collection basin of said first cooling unit, said heat exchange fluid from said power generating system being arranged to flow through said first heat exchanging pipes of said first cooling unit and said second heat exchanging pipes of said second cooling unit in such a manner that said heat exchange fluid is arranged to perform highly efficient heat exchanging process with said cooling water for lowering a temperature of said heat exchange fluid, a predetermined amount of air being drawn from said air inlet side for performing heat exchange with said cooling water flowing through said first fill material unit and said second fill material unit for lowering a temperature of said cooling water, said air having absorbed said heat from said cooling water being discharged out of said first fill material unit and said second fill material unit through said air outlet side.
 2. The power plant, as recited in claim 1, wherein said evaporative cooling system comprises a plurality of multiple-effect evaporative condensers accommodated in said tower housing, said multiple-effect evaporative condensers are spacedly arranged in said tower housing in two rows and a plurality of columns, such that for each row of said multiple-effect evaporative condensers, a longitudinal axis of each of said multiple-effect evaporative condensers is substantially parallel to each other, while for each column of said multiple-effect evaporative condensers, a longitudinal axis of each of said multiple-effect evaporative condensers is substantially aligned.
 3. The power plant, as recited in claim 2, wherein each two of said adjacent multiple-effect evaporative condensers is grouped to form an evaporative condenser unit, said evaporative cooling unit further comprising a plurality of top sealing members each of which is connected between two of said first water collection basins of said two adjacent multiple-effect evaporative condensers for each said evaporative condenser unit.
 4. The power plant, as recited in claim 2, wherein said pumping device is positioned in said bottom water collection basin at said air inlet side, and is connected to said first water collection basin through a water pipe.
 5. The power plant, as recited in claim 2, wherein each of said multiple-effect evaporative condensers further comprises at least one filter arrangement detachably supported between said first cooling unit and said second cooling unit.
 6. The power plant, as recited in claim 5, wherein said filter arrangement comprises a main panel, a plurality of through filtering holes spacedly formed on said main panel, a filtering net attached on a bottom side of said main panel, and a supporting member provided at a bottom side of said main panel.
 7. The power plant, as recited in claim 6, wherein said filter arrangement further comprises a cleaning arrangement which comprises a plurality of guiding pulleys provided at two ends of said filtering net, a plurality of cleaning nozzles supported at a position adjacent to said guiding pulleys respectively.
 8. The power plant, as recited in claim 7, wherein said filtering net is configured by stainless steel.
 9. The power plant, as recited in claim 2, wherein said first water collection basin has a first stabilizing compartment connected to said pumping device, a first heat exchanging compartment provided adjacent to and communicated with said first stabilizing compartment via a first water channel, wherein said first heat exchanging pipes are immersed in said first heat exchanging compartment, said cooling water pumped by said pumping device being guided to flow into said first stabilizing compartment through said first water channel.
 10. The power plant, as recited in claim 9, wherein said first water collection basin has a first inner sidewall, a first outer sidewall, a first partitioning wall, a first bottom plate, and a first passage plate, said first partitioning wall being provided between said first inner sidewall and said first outer sidewall, and dividing said first water collection basin into said first stabilizing compartment and said first heat exchanging compartment, said first water channel being formed on said first partitioning wall along a longitudinal direction thereof, said first stabilizing compartment being formed between said first inner sidewall, said first partitioning wall, and said first bottom plate, said first heat exchanging compartment being formed by said first partitioning wall, said first outer sidewall, and said first passage plate.
 11. The power plant, as recited in claim 10, wherein said first passage plate has a plurality of first passage holes for allowing said cooling water contained in said first heat exchanging compartment to fall into said first fill material unit.
 12. The power plant, as recited in claim 11, wherein each of said multiple-effect evaporative condensers comprises a flow control mechanism which comprises at least one control plate movably provided underneath said first passage plate of said first water collection basin, at least one driving member connected to said control plate for driving said control plate to move in a horizontal and reciprocal manner, and a plurality of securing members, said control plate having a plurality of control holes spacedly distributed thereon, said securing members being mounted on said first water collection basin and arranged to normally exert an upward biasing force toward said control plate so as to maintain a predetermined distance between said control plate and said first passage plate.
 13. The power plant, as recited in claim 12, wherein each first water collection basin further has a pair of first securing slots formed at lower portions of said first partitioning wall and said first outer sidewall respectively, each of said first securing slots being elongated along a longitudinal direction of said first water collection basin, wherein said securing members are mounted in said first securing slots respectively.
 14. The power plant, as recited in claim 13, wherein said flow control mechanism further comprises an automated control system comprising a central control unit, a connecting member connected between said central control unit and said driving member, and a sensor provided in said first water collection basin and electrically connected to said central control unit.
 15. The power plant, as recited in claim 2, wherein said second water collection basin has a second heat exchanging compartment, wherein said second heat exchanging pipes are immersed in said second heat exchanging compartment.
 16. The power plant, as recited in claim 15, wherein said second water collection basin has a second inner sidewall, a second outer sidewall, and a second passage plate, wherein said second heat exchanging compartment is defined within said second inner sidewall, said second outer sidewall, and said second passage plate, said second passage plate having a plurality of second passage holes for allowing said cooling water to pass therethrough.
 17. The power plant, as recited in claim 16, wherein said second water collection basin further has a pair of second securing slots formed at lower portions of said second inner side wall and said second outer sidewall respectively, said securing members being mounted in said second securing slots respectively.
 18. The power plant, as recited in claim 2, wherein each of said multiple effect evaporative condensers further comprises a supplementary water supply unit which comprises a plurality of water level sensors provided in said first water collection basin and said second water collection basin respectively, a plurality of supplemental water pipes extended between said water pipe and said first water collection basin and said second water collection basin respectively, and a plurality of water control valves provided in said supplemental water pipes respectively for controlling a flow of water therein.
 19. The power plant, as recited in claim 2, wherein each of said first heat exchanging pipes comprises a first pipe body and a plurality of first retention members spacedly formed in said first pipe body, and a plurality of first heat exchanging fins extended from an inner surface of said first pipe body.
 20. The power plant, as recited in claim 19, wherein each of said first pipe bodies has two curved side portions and a substantially flat mid portion extending between said two curved side portions to form rectangular cross sectional shape at said mid portion and two semicircular cross sectional shapes at two curved side portions of said first heat exchanging pipe.
 21. The power plant, as recited in claim 20, wherein said first retention members are spacedly distributed in said flat mid portion along a transverse direction of said corresponding first pipe body so as to form a plurality of first pipe cavities, each of said first heat exchanging fins being extended from an inner surface of said first pipe body.
 22. The power plant, as recited in claim 2, wherein each of said second heat exchanging pipes comprises a second pipe body and a plurality of second retention members spacedly formed in said second pipe body, and a plurality of second heat exchanging fins extended from an inner surface of said second pipe body.
 23. The power plant, as recited in claim 22, wherein each of said second pipe bodies has two curved side portions and a substantially flat mid portion extending between said two curved side portions to form rectangular cross sectional shape at said mid portion and two semicircular cross sectional shapes at two curved side portions of said second heat exchanging pipe.
 24. The power plant, as recited in claim 2, wherein each of said heat exchanging pipes has a thin oxidation layer formed on an exterior surface and an interior surface thereof for preventing further corrosion of said relevant heat exchanging pipe.
 25. The power plant, as recited in claim 24, wherein each of said heat exchanging pipes has a thin layer of polytetrafluoroethylene formed on an exterior surface thereof to prevent unwanted substances from attaching on said corresponding exterior surface.
 26. The power plant, as recited in claim 2, wherein said first cooling unit further comprises a first guiding system connected to said first heat exchanging pipes to divide said first heat exchanging pipes into at least two piping groups.
 27. The power plant, as recited in claim 26, wherein said first guiding system comprises a plurality of first inlet collection pipes extended between outer ends of said first heat exchanging pipes, a first outlet pipe extended between inner ends of said first heat exchanging pipes, wherein said first outlet pipe is extended at a position between said two first inlet collection pipes.
 28. The power plant, as recited in claim 27, wherein said first heat exchanging pipes are inclinedly and downwardly extended from said first inlet collection pipe toward said first outlet pipe.
 28. The power plant, as recited in claim 27, wherein said first guiding system further comprises a plurality of first heat exchanging fins extended between each two adjacent first heat exchanging pipes.
 29. The power plant, as recited in claim 2, wherein said second cooling unit further comprises a second guiding system connected to said second heat exchanging pipes to divide said second heat exchanging pipes into at least two piping groups.
 30. The power plant, as recited in claim 29, wherein said second guiding system comprises a plurality of second inlet collection pipes extended between outer ends of said second heat exchanging pipes, a second outlet pipe extended between inner ends of said second heat exchanging pipes, wherein said second outlet pipe is extended at a position between said two second inlet collection pipes.
 31. The power plant, as recited in claim 30, wherein said second guiding system further comprises a plurality of second heat exchanging fins extended between each two adjacent second heat exchanging pipes.
 32. The power plant, as recited in claim 31, wherein said second heat exchanging pipes are inclinedly and downwardly extended from said second inlet collection pipe toward said second outlet pipe. 